Allen, in footage obtained by TMZ, said Leno appeared happy and in good spirits.
"He's feeling better," Allen said in the video. "We did some jokes, which is what we do. We commiserated."
"He's handsome and he's happy," Allen said. "The hospital is doing a great job taking care of him."
Allen's visit comes three days after Leno issued his own statement on Nov. 14 regarding the incident.
"I got some serious burns from a gasoline fire," Leno said in a statement. "I am ok. Just need a week or two to get back on my feet."
The Grossman Burn Center in Los Angeles also affirmed that Leno is fairing well following the burns.
"Jay Leno is in stable condition," the statement read, per KTLA, "and he's receiving treatment here at the burn center to his face and his hands from a gasoline accident in his garage over the weekend."
His doctor, Dr. Peter Grossman, told NBC Los Angeles that he expects the 72-year-old to make a full recovery.
"He's walking around and he's cracking jokes. I can tell you he's incredibly kind to our nursing staff," Grossman shared. "He's been appreciative of everybody here and he's an ideal patient, and one who understands the seriousness of his injury."